Modeling Shear Behavior of Woven Fabric Thermoplastic Composites for Crash Simulations
- PDF / 3,007,612 Bytes
- 27 Pages / 439.37 x 666.142 pts Page_size
- 52 Downloads / 233 Views
Modeling Shear Behavior of Woven Fabric Thermoplastic Composites for Crash Simulations Bilal Ahmad1 · Xiangfan Fang1 Received: 16 July 2020 / Accepted: 2 November 2020 © The Author(s) 2020
Abstract Woven fabric thermoplastic composites possess high specific strength and stiffness along with thermoformability. To utilize the full potential of these materials to achieve better crash-safe designs in automotive structural parts, the measurement of non-linear shear behavior and its material modeling for FEM simulations is required. The standard testing method was used to measure the pure shear behavior of woven fabric composites. These results were compared with the shear behavior of material in the presence of normal stresses along the fiber direction. Tensile and compression cyclic testing of ± 45° laminate were carried out to measure the stiffness degradation and hardening of the material in the presence of tensile normal and compression normal stress. A methodology is proposed for taking into account the differences in shear behavior under different loading directions in an FEM simulation. Based on the experimental evidence, improvements in the mathematical description of plasticity and damage in continuum damage mechanics models are proposed. The model was implemented as a user-defined material subroutine (VUMAT) for Abaqus. The experimental results from coupon tests were used to verify the results of a single element simulation. Finally, a three-point bending test was used to validate the predictions of the user material model. Keywords Organo sheet · Woven fabric composite · Shear testing · Modeling · Crash simulation · Impact
1 Introduction Woven fabric composites are increasingly being used in the automotive sector due to their high specific strength, specific stiffness, and specific energy absorption capabilities. The woven fabric thermoplastic composites, so-called Organo sheets, can be thermoformed, which makes them particularly feasible for series production with reduced production
* Xiangfan Fang Xiangfan.fang@uni‑siegen.de Bilal Ahmad Bilal.ahmad@uni‑siegen.de 1
University of Siegen, 57076 Siegen, Germany
13
Vol.:(0123456789)
Applied Composite Materials
costs. To use these materials in automotive applications, crashworthiness requirements must be met. The lightweight potential of these materials is achieved by aligning the fibers in the direction of the load; this, however, leads to catastrophic brittle fracture at low strains. Sometimes, it might be desirable to achieve ductile or high failure strain behavior which can be achieved by angle-ply laminates. Furthermore, a weight-efficient design in which fibers are aligned along one particular direction might not be in the direction of crash forces. Therefore, the ability to predict the crash behavior of angle-ply laminates through FEM simulations, then, is just as important as it is along the fiber direction. Angle-ply laminates demonstrate non-linear behavior and high strains to failure. This effect is more pronounced in the tensile/compre
Data Loading...
